Jahvid Best, a former running back for the Detroit Lions, is suing the National Football League and helmet maker Riddell over concussion problems that shortened his professional career.

In a lawsuit filed on Tuesday in Wayne County (Michigan) Circuit Court, Best alleges the league was aware of the risks of traumatic brain injury, but ”deliberately ignored and actively concealed” the information, the Associated Press (AP) reports. Riddell, the suit claims, made defective helmets and failed to inform the players of the long-term effects of concussions.

”The NFL, like the sport of boxing, was aware of the health risks associated with repetitive blows producing sub-concussive and concussive results and the fact that some members of the NFL players population were at significant risk of developing long-term brain damage and cognitive decline as a result,” the legal complaint states. Further, the AP writes, the league “turned a blind eye to the risk and failed to warn and/or impose safety regulations governing this health and safety problem.”

The adverse effects of concussions have become a serious concern in all levels of football, from youth to professional. ESPN reported that a federal judge recently denied preliminary approval of a $765 million settlement of retired NFL players’ concussion claims, for fear that the amount may not be enough to cover claims from 20,000 retired players. If approved, the settlement would award varying amounts depending on such factors as the player’s age, length of career, and severity and type of neurological symptoms.

Jahvid Best was a first-round draft pick for the Lions in 2010, and in his rookie season he accounted for 1,000-plus yards and six touchdowns. But in 2011, he played in only six games, after he suffered the third concussion of his football career. He was inactive for the entire 2012 season and was released by Detroit in July 2013.

Best’s attorney said that the full extent of “the injuries to the brain may not manifest themselves for a number of years,” though Best has already shown signs of concussion syndrome, according to the AP. Court documents say that Best seeks compensatory and punitive damages from the NFL and Riddell, along with economic and non-economic damages.